Audio reproduction equipment

Abstract

The present invention is an audio playback device, comprising: a signal processing circuit that generates multi-channel audio data; an attenuation control unit that is connected to the signal processing circuit and controls the attenuation of the audio data of each channel; and a speaker device that is driven by the multi-channel audio signal from the attenuation control unit and has a multi-channel speaker including a woofer. The attenuation control unit is configured to: estimate the total current value of the current flowing to the speaker device according to the audio data value for each channel; control the attenuation amount so that the estimated total current value does not exceed a predetermined specified value; and control the attenuation amount according to a predetermined priority order so as to maintain the relationship between the channels.

Description

Technical Field

[0001] The present technology relates to an audio reproduction device including a multi-channel speaker. Background Art

[0002] In order to produce a realistic feeling, many formats for audio reproduction systems such as so-called stereo systems, 3D audio, VR audio, etc. have been proposed and designed to perform multi-channel audio reproduction. In order to perform multi-channel audio reproduction, an audio reproduction device with integrated multiple speakers is used to facilitate portability and outdoor music enjoyment.

[0003] In the case of such an audio reproduction device, a DC power supply may be constituted by a commercial power supply, or a battery power supply may be used for operation. The power supply has a protection function of cutting off the power supply when a load current of a predetermined value or more flows. Therefore, also in the case of an audio reproduction device having a multi-channel speaker, when a current of a set value or more flows through the multi-channel speaker, the power supply is cut off. The cut-off is activated by turning off a switching element, blowing a fuse, or the like.

[0004] Patent Document 1 describes that, in a case where the total value of current consumption of multiple channels exceeds a predetermined value, the upper limit value of the limiter unit is lowered preferentially from a channel having the largest predicted current consumption.

[0005] Citation List

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-217295 Summary of the invention

[0008] Problems to be solved by the present invention

[0009] In the case described in Patent Document 1, since the upper limit value of the limiter unit is lowered preferentially from the channel having the largest predicted current consumption, there is a problem in that the effect of multi-channel reproduction is impaired.

[0010] Therefore, an object of the present technology is to provide an audio reproducing device which prevents the acoustic effect of multi-channel audio reproduction from being impaired as much as possible while preventing power cutoff due to overcurrent.

[0011] Solution to the problem

[0012] The present technology provides an audio reproduction device, comprising:

[0013] a signal processing circuit that generates multi-channel audio data;

[0014] an attenuation amount control unit connected to the signal processing circuit and controlling an attenuation amount of the audio data of each channel; and

[0015] a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer,

[0016] wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value that has been set in advance, and

[0017] The attenuation amount is controlled according to the priority that has been set in advance in such a manner that the relationship between the channels is maintained.

[0018] In addition, the present technology provides an audio reproduction device, comprising:

[0019] a signal processing circuit that generates multi-channel audio data;

[0020] an attenuation amount control unit connected to the signal processing circuit and controlling an attenuation amount of the audio data of each channel; and

[0021] a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer,

[0022] wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value allowed by the power supply, and

[0023] The attenuation amount control unit performs a first determination process for determining whether the total current value exceeds a predetermined value when the input data to the woofer is attenuated within a range up to zero, and attenuates the input data to the woofer by a required amount when it is determined that the total current value does not exceed the predetermined value, and

[0024] In the case where it is determined in the first determination processing that the total current value exceeds the predetermined value, the second determination processing for determining whether the total current value exceeds the predetermined value is performed, while attenuating the input data for the woofer to substantially zero and then attenuating the input data for the speakers other than the woofer within a range up to the value that has been set, and in the case where it is determined that the total current value does not exceed the predetermined value, the input data for the speakers other than the woofer is attenuated by a required amount.

[0025] Effects of the Invention

[0026] According to at least one embodiment, the present technology can prevent power from being cut off during audio reproduction. In this case, the acoustic effect of audio reproduction can be prevented from being damaged. Note that the effects described here are not necessarily restrictive, and the effects of the present invention may be any effects described in the present technology, or may be effects different from those effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a block diagram of one embodiment of the present technology.

[0028] Figure 2 is a block diagram of an example of a total current controller according to the first embodiment of the present technology.

[0029] Figure 3 (a), 3(b), and 3(c) are a top view, a perspective view, and a partial cross-sectional view illustrating the appearance of one embodiment of the present technology.

[0030] Figure 4 is a flowchart for illustrating an example of total current control. DETAILED DESCRIPTION

[0031] Embodiments of the present technology will be described below with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present technology, and the content of the present technology is not limited to these embodiments, etc. In addition, in the following description, for the purpose of preventing the illustration from being complicated, only some components may be assigned reference numerals, or some components may be illustrated in a simplified manner.

[0032] Reference Figure 1 The overall configuration of an embodiment of the present technology is described. Input data is supplied to a decoder 1. The input data is stream data of a predetermined format of stereo audio such as immersive audio, and the decoder 1 converts the stream data into multi-channel audio data. In an embodiment, the decoder 1 outputs 10-channel audio data. Immersive audio can perform audio reproduction in a desired manner in a height direction and in a plane to provide a realistic feeling to the listener.

[0033] The output from the decoder 1 is supplied to the post-processor 2. The post-processor 2 corrects the signal output from the decoder 1 into a signal taking into account the characteristics of the speaker and the like. The signal output from the post-processor 2 is supplied to the total current controller 3. The total current controller 3 functions as an attenuation amount control unit that attenuates the signal so that the power supply is not cut off.

[0034] The signal output from the total current controller 3 is supplied to the amplifier functional block 4. The amplifier functional block 4 is connected to a speaker device 5 having, for example, seven channels. The speaker device 5 is composed of seven speakers arranged as described later. The seven speakers are a top left speaker TL, a top right speaker TR, a top center speaker TC, a side left speaker SL, a side right speaker SR, a side center speaker SC, and a woofer WF. The speakers other than the woofer WF are full-range reproduction speakers. Note that, as indicated by the surrounding dotted lines, the decoder 1, the post-processor 2, and the total current controller 3 constitute a digital signal processor (DSP).

[0035] Reference Figure 2 The total current controller 3 is described. The total current controller 3 supplies a signal to the speaker device 5 via the delay circuit 31 and the signal attenuation unit 32. The current estimation unit 33 estimates the total current value flowing through the speaker device 5 according to the value of the audio data of each channel.

[0036] The output from the current estimation unit 33 is supplied to the attenuation amount determination unit 34. The attenuation amount determination unit 34 generates a control signal for controlling the attenuation amount of the data for each channel so that the estimated total current value does not exceed a predetermined value set in advance. A control signal for indicating the attenuation amount is supplied from the attenuation amount determination unit 34 to the signal attenuation unit 32.

[0037] The delay circuit 31 delays the data by the time required to generate a control signal for controlling the attenuation amount. In this embodiment, the total current controller 3 is designed to perform control for each sample of the audio data. That is, the control signal generated by the total current controller 3 is applied to the target data to prevent any delay of one sample. The sampling period of the audio data is, for example, 48kHz. It is noted that, in the case where the current estimation unit 33 performs processing in units of one sample, the attenuation amount determination unit 34 and the signal attenuation unit 32 can perform processing in units of arbitrary time periods (update periods) other than for each sample. In that case, the delay circuit 31 has a delay time of the arbitrary time period.

[0038] Reference Figure 3 (a) Figure 3 (b) and Figure 3 (c) An embodiment of the present technology including the speaker device 5 is described. Figure 3 (a) is a plan view of an audio reproduction device, Figure 3 (b) is a perspective view of the audio reproduction device as seen from the listener side, and Figure 3 (c) is a partial cross-sectional view of the audio reproduction device viewed from the listener side.

[0039] A top right speaker TR, a top left speaker TL, and a top center speaker TC are provided on the top surface of the cylindrical housing 11 of the audio reproduction device. The sound radiation direction of these speakers is set to be slightly inclined upward from the vertical upward direction. These speakers TR, TL, and TC contribute to the positioning of the sound image at a predetermined position in the space above the audio reproduction device.

[0040] have Figure 1 A circuit board of the electrical configuration in is mounted inside the housing 11. Three speakers are arranged at an angle of about 120°. The top left speaker TL and the top right speaker TR are located on the listener side. Note that the audio reproduction device has a logo mark of the manufacturer on the front thereof, and the audio reproduction device is placed so that the logo mark faces the listener side.

[0041] The side left speaker SL, the side right speaker SR, and the side center speaker SC are arranged at an intermediate height position on the housing 11. The three speakers are arranged at an angle interval of about 120°, and each of their sound radiation directions is set to an outward direction orthogonal to the tangent line of the outer peripheral surface of the housing 11. The side left speaker SL and the side right speaker SR are arranged symmetrically with respect to the listener side. The woofer WF is arranged on the bottom side of the housing 11, and the sound radiation direction is upward. Note that other than the speaker, it is possible to use Figure 3 Speaker arrangements other than those shown.

[0042] Reference Figure 4 The flowchart in describes the processing performed by the total current controller 3 in one embodiment of the present technology. The total current controller 3 performs the total current control processing for each sample of the audio data. The total current is the sum of the currents flowing through the speakers of the speaker device 5. Figure 4 In the following description, the total current is referred to as aggregate current.

[0043] Step ST1: Calculate the required attenuation before the next sample.

[0044] Step ST2: The current estimation unit 33 estimates the load current of the speaker according to the multi-channel input data.

[0045] Step ST3: It is determined whether the aggregate current of the load current does not exceed a predetermined value Ix. The predetermined value Ix is the maximum current value allowed by the power supply device used or a current value slightly smaller than the maximum current value, and is, for example, 8.2 A. In the case where it is determined that the aggregate current does not exceed the predetermined value Ix, since attenuation is not required, the process returns to step ST1.

[0046] Step ST4: If the determination result in step ST3 indicates that the aggregate current exceeds Ix, it is determined whether the aggregate current can be reduced below Ix by attenuating the woofer WF to -∞dB (first determination processing). -∞dB indicates the attenuation amount that changes the data value to zero.

[0047] Step ST5: In the case where it is determined in step ST4 (first determination processing) that the aggregate current value can be reduced to below Ix, a required attenuation amount is applied to the signal to be input to the woofer WF. Then, the processing returns to step ST1.

[0048] Step ST6: When it is determined in step ST4 (first determination processing) that the aggregate current cannot be reduced below Ix (attenuation alone for the woofer WF is insufficient), attenuation of -∞dB is applied to the signal to be input to the woofer WF.

[0049] Step ST7: After step ST6, it is determined whether the aggregate current can be reduced below Ix by further applying attenuation (within a first range up to -6 dB) to the signal to be input to the first group of multiple speakers (side center speaker SC and top center speaker TC) (second determination process). The first group includes speakers located substantially in the center when viewed from the listener side.

[0050] Step ST8: In the case where it is determined in step ST7 (second determination processing) that the aggregate current value can be reduced to below Ix, a required attenuation amount is applied to the signal to be input to the first group (side center speaker SC and top center speaker TC). Then, the processing returns to step ST1.

[0051] Step ST9: When it is determined in step ST7 (second determination processing) that the aggregate current cannot be reduced below Ix (attenuation only for the woofer WF, side center speaker SC, and top center speaker TC is insufficient), an attenuation of -6dB (the maximum value in the first range) is applied to the signal to be input to the first group (side center speaker SC and top center speaker TC).

[0052] Step ST10: After step ST9, determine whether the aggregate current can be reduced to below Ix by further applying attenuation (within a second range of up to -3dB) to the signal to be input to the second group (side right speaker SR and side left speaker SL, and top left speaker TL and top right speaker TR) (third determination processing).

[0053] Step ST11: In the case where it is determined in step ST10 (third determination processing) that the aggregate current value can be reduced to below Ix, a required attenuation amount is further applied to the signal to be input to the second group (side right speaker SR and side left speaker SL, and top left speaker TL and top right speaker TR). Then, the processing returns to step ST1.

[0054] Step ST12: In the case where it is determined in step ST10 (third determination processing) that the aggregate current cannot be reduced below Ix (i.e., attenuation only for the woofer WF, the side center speaker SC, the top center speaker TC, the side right speaker SR, the side left speaker SL, the top left speaker TL, and the top right speaker TR is insufficient), attenuation of -3 dB (maximum value in the second range) is applied to the signals to be input to the side right speaker SR, the side left speaker SL, the top left speaker TL, and the top right speaker TR. The maximum value in the second range is set so that the attenuation amount is smaller than the maximum value in the first range.

[0055] Step ST13: Attenuation is uniformly applied to the signals to be input to all the speakers until the aggregate current drops below Ix. Then, the process returns to step ST1.

[0056] As described above, in the embodiment of the present technology, the attenuation amount is controlled according to the priority that has been set in advance, and the attenuation amount is equalized within the same group so that the relationship between the channels is maintained. As a result of the attenuation amount control, the expected effect of audio reproduction (realistic feeling, spatial expansion, etc.) can be prevented from being damaged.

[0057] Although the embodiments of the present technology have been specifically described above, the present technology is not limited to the above embodiments, and various modifications can be made based on the technical ideas of the present technology. For example, multi-channel speakers other than woofers can be divided into three or more groups. The present technology can be applied not only to seven channels but also to multi-channel audio such as 5.1 channels or 11.1 channels. Moreover, audio reproduction can be performed simultaneously with video reproduction.

[0058] The configurations, methods, processes, shapes, materials, numerical values, etc. described in the above embodiments are merely examples, and configurations, methods, processes, shapes, materials, numerical values, etc. different from those described above may be used when necessary. The above embodiments and modified examples may be combined as appropriate.

[0059] The present technology may also be configured as described below.

[0060] (1) An audio reproduction device comprising:

[0061] a signal processing circuit, the signal processing circuit generating multi-channel audio data;

[0062] an attenuation amount control unit connected to the signal processing circuit and controlling an attenuation amount of audio data of each channel; and

[0063] a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer,

[0064] wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value that has been set in advance, and

[0065] The attenuation amount is controlled according to the priority that has been set in advance in such a manner that the relationship between the channels is maintained.

[0066] (2) The audio reproducing device according to (1), wherein the attenuation amount control unit performs control for each sample of the audio data of each channel.

[0067] (3) The audio reproduction device according to (1) or (2), wherein

[0068] The multi-channel speaker is divided into a group of the woofer and a plurality of speakers other than the woofer,

[0069] attenuation of input data for the woofer is ranked first, and attenuation of input data for the group of the plurality of speakers excluding the woofer is ranked second,

[0070] setting an attenuation amount of input data for the woofer in such a manner as to change the input data to zero to the greatest extent, and

[0071] The attenuation amount for the input data of the group is set to a value within a range that has been set and is substantially equal among the plurality of speakers.

[0072] (4) The audio reproducing device according to any one of (1) to (3), wherein

[0073] The plurality of speakers other than the woofer are divided into a first group and a second group,

[0074] The attenuation of the input data for the woofer is ranked first, the attenuation of the input data for the first group is ranked second, and the attenuation of the input data for the second group is ranked third,

[0075] setting an attenuation amount of input data for the woofer in such a manner as to change the input data to zero to the greatest extent,

[0076] The attenuation amount for the input data of the first group is set to a value within a first range that has been set and is substantially equal among the plurality of speakers, and

[0077] The attenuation amount for the second group of input data is set to a value within the second range that has been set and is substantially equal among the plurality of speakers.

[0078] (5) The audio reproducing device according to (4), wherein a maximum value in the second range is smaller than a maximum value in the first range.

[0079] (6) The audio reproduction device according to (4), wherein the first group contributes less to sound image localization in space than the second group.

[0080] (7) The audio reproducing device according to (4), wherein

[0081] The first group includes a speaker located substantially centrally when viewed from the listener side, and

[0082] The second group includes speakers located on the left and right when viewed from the listener's side.

[0083] (8) An audio reproduction device comprising:

[0084] a signal processing circuit, the signal processing circuit generating multi-channel audio data;

[0085] an attenuation amount control unit connected to the signal processing circuit and controlling an attenuation amount of audio data of each channel; and

[0086] a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer,

[0087] wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value allowed by the power supply, and

[0088] The attenuation amount control unit performs a first determination process for determining whether the total current value exceeds the predetermined value when the input data to the woofer is attenuated within a range up to zero, and attenuates the input data to the woofer by a required amount when it is determined that the total current value does not exceed the predetermined value, and

[0089] In a case where it is determined in the first determination processing that the total current value exceeds the predetermined value, while attenuating the input data to the woofer to substantially zero and then attenuating the input data to the speakers other than the woofer within a range up to a value that has been set, a second determination processing for determining whether the total current value exceeds the predetermined value is performed, and in a case where it is determined that the total current value does not exceed the predetermined value, the input data to the speakers other than the woofer is attenuated by a required amount.

[0090] (9) The audio reproducing device according to (8), wherein

[0091] The plurality of speakers other than the woofer are divided into a first group and a second group,

[0092] performing the second determination process on the first group, and

[0093] When it is determined in the second determination process that the total current value exceeds the predetermined value, the input data for the first group of speakers is attenuated to a maximum value within a set range, and then the input data for the second group of speakers is attenuated within a range up to the set value.

[0094] Reference numerals list

[0095] 1 Decoder

[0096] 3 Total current controller

[0097] 5 Speaker equipment

[0098] 31 Delay Circuit

[0099] 32 signal attenuation units

[0100] 33 Current estimation unit

[0101] 34 Attenuation determination unit

Claims

1. An audio reproduction device, comprising: a signal processing circuit, the signal processing circuit generating multi-channel audio data; an attenuation control unit connected to the signal processing circuit and controlling an attenuation amount of the audio data of each channel; as well as a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer, wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value that has been set in advance, and The attenuation amount is controlled according to a preset priority so as to maintain the relationship between the channels, wherein The multi-channel speaker is divided into a group of the woofer and a plurality of speakers other than the woofer, attenuation of input data for the woofer is ranked first, and attenuation of input data for the group of the plurality of speakers excluding the woofer is ranked second, setting an attenuation amount of input data for the woofer in such a manner as to change the input data to zero to the greatest extent, and The attenuation amount for the input data of the group is set to a value within a range that has been set and is substantially equal among the plurality of speakers. 2 . The audio reproducing device according to claim 1 , wherein the attenuation amount control unit performs control on each sample of the audio data of each channel.

3. The audio reproduction device according to claim 1, wherein The plurality of speakers other than the woofer are divided into a first group and a second group, The attenuation of the input data for the woofer is ranked first, the attenuation of the input data for the first group is ranked second, and the attenuation of the input data for the second group is ranked third, setting an attenuation amount of input data for the woofer in such a manner as to change the input data to zero to the greatest extent, The attenuation amount for the input data of the first group is set to a value within a first range that has been set and is substantially equal among the plurality of speakers, and The attenuation amount for the second group of input data is set to a value within the second range that has been set and is substantially equal among the plurality of speakers. The audio reproduction device according to claim 3 , wherein a maximum value in the second range is smaller than a maximum value in the first range.

5. The audio reproduction device of claim 3, wherein the first group contributes less to sound image localization in space than the second group.

6. The audio reproduction device according to claim 3, wherein The first group includes a speaker located substantially centrally when viewed from the listener side, and The second group includes speakers located on the left and right when viewed from the listener's side.

7. An audio reproduction device comprising: a signal processing circuit, the signal processing circuit generating multi-channel audio data; an attenuation control unit connected to the signal processing circuit and controlling an attenuation amount of the audio data of each channel; as well as a speaker device driven by the multi-channel audio signal from the attenuation amount control unit and having a multi-channel speaker including a woofer, wherein the attenuation amount control unit estimates a total current value flowing through the speaker device according to the audio data value of each channel, and controls the attenuation amount in such a manner that the estimated total current value does not exceed a predetermined value allowed by the power supply, and The attenuation amount control unit performs a first determination process for determining whether the total current value exceeds the predetermined value when the input data to the woofer is attenuated within a range up to zero, and attenuates the input data to the woofer by a required amount when it is determined that the total current value does not exceed the predetermined value, and In a case where it is determined in the first determination process that the total current value exceeds the predetermined value, while attenuating the input data for the woofer to substantially zero, and then attenuating the input data for the plurality of speakers other than the woofer within a range up to a value that has been set, a second determination process for determining whether the total current value exceeds the predetermined value is performed, and in a case where it is determined that the total current value does not exceed the predetermined value, the input data for the plurality of speakers other than the woofer are attenuated by a required amount, wherein the attenuation amounts of the input data for the plurality of speakers other than the woofer are set to values ​​within the range that has been set and are substantially equal among the plurality of speakers.

8. The audio reproduction device according to claim 7, wherein The plurality of speakers other than the woofer are divided into a first group and a second group, performing the second determination process on the first group, and When it is determined in the second determination process that the total current value exceeds the predetermined value, the input data for the first group of speakers is attenuated to a maximum value within a set range, and then the input data for the second group of speakers is attenuated within a range up to the set value.

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